About My Code

Faking num lock, caps lock and scroll lock leds

Giorgi — Thu, 10 May 2012 12:21:55 +0000

Introduction Some time ago I came across a post where the author wanted to turn on and off num lock, cap lock and scroll lock led light without actually toggling their state. This sounded challenging and impossible but after some googling I found a piece of code in C for achieving exactly what I was [...]

Faking num lock, caps lock and scroll lock leds

Building Expression Evaluator with Expression Trees in C# – Improving the Api

Giorgi — Wed, 18 Apr 2012 09:03:09 +0000

In previous part we added support for variables but it has a big disadvantage: values of the variables are bound by position and not by name. This means that you should pass values for the variables in the same order as they appear in the expression. On the other hand binding by name has following advantages: If you change the expression you do not have to worry about keeping order of the variables you pass in sync. So in this post we are going to change expression evaluator to bind parameters by name. We will also add a new overload for better performance when we need to evaluate same expression with different parameter values.

Building Expression Evaluator with Expression Trees in C# – Improving the Api

Using Reactive Extensions for Streaming Data from Database

Giorgi — Mon, 02 Apr 2012 22:04:03 +0000

You have probably heard about Reactive Extensions, a library from Microsoft that greatly simplifies working with asynchronous data streams and allows to query them with Linq operators. There are many different scenarios where using rx results in a much more simple and flexible code. This post demonstrates how to use reactive extensions for loading data [...]

Using Reactive Extensions for Streaming Data from Database

Building Expression Evaluator with Expression Trees in C# – Part 3

Giorgi — Wed, 21 Mar 2012 08:14:52 +0000

In part two of this series we built an expression evaluator capable of parsing expressions with parentheses. In this part we are going to add support for expression with variables.

Building Expression Evaluator with Expression Trees in C# – Part 3

Building Expression Evaluator with Expression Trees in C# – Part 2

Giorgi — Tue, 28 Feb 2012 07:41:10 +0000

Introduction In previous post I showed how to build a simple expression evaluator using expression trees. Although it works fine it has some drawbacks: It does not support parentheses. It does not support variables. In some cases the result can be wrong as the parser is not using left to right parsing. It is compiling [...]

Building Expression Evaluator with Expression Trees in C# – Part 2

Building Expression Evaluator with Expression Trees in C# – Part 1

Giorgi — Thu, 23 Feb 2012 13:00:15 +0000

Introduction This is first part of a series about writing expression evaluator in C#. Even though there are several of them available already I decided to write my own as this one is based on expression trees and is very simple. The evaluator supports numeric expressions as well as expression with parameters. In this part [...]

Building Expression Evaluator with Expression Trees in C# – Part 1

Building Expression Evaluator with Expression Trees in C# – Table of Contents

Giorgi — Tue, 21 Feb 2012 17:43:45 +0000

This is table of contents for Building Expression Evaluator with Expression Trees in C# series. We are going to build a simple mathematical expression evaluator in C# using expression trees. The library supports simple expressions such as 2.5+5.9, 17.89-2.47+7.16, 5/2/2+1.5*3+4.58, expressions with parentheses (((9-6/2)*2-4)/2-6-1)/(2+24/(2+4)) and expressions with variables: At the end of the series full [...]

Building Expression Evaluator with Expression Trees in C# – Table of Contents

Dynamic ViewState in ASP.Net WebForms – Part 2

Giorgi — Tue, 31 Jan 2012 08:26:35 +0000

In previous post I showed an approach combining DynamicObject with ViewState for accessing ViewState members using dynamic properties instead of string indexes. However that approach had some disadvantages: It is tied some a concrete base page class. It does not have all the properties/methods of StateBag class Mixing ViewState and ViewBag can be confusing for [...]

Dynamic ViewState in ASP.Net WebForms – Part 2

Dynamic ViewState in ASP.Net WebForms

Giorgi — Tue, 17 Jan 2012 09:19:01 +0000

If you have worked with ASP.Net MVC 3 you are probably aware of ViewBag property which allows you to pass data from Controller to View by using dynamic properties instead of hard coding strings. While the properties still are not strongly typed and compiler does not check them it can provide an advantage. For example [...]

Dynamic ViewState in ASP.Net WebForms

AppDomain.AssemblyResolve Event Tips

Giorgi — Wed, 04 Jan 2012 09:21:51 +0000

AppDomain.AssemblyResolve event can be used to load referenced assemblies at runtime. This can be useful in multiple scenarios: you can use it to load a library from a different location or load a library based on bitness or load a library which is embedded in the executable file. In all cases there are some tips [...]

AppDomain.AssemblyResolve Event Tips